However, a PHE report in 2015 said e-cigarettes should not be viewed in the same way as smoking.

It said "best estimates show e-cigarettes are 95% less harmful to your health than normal cigarettes, and when supported by a smoking cessation service help most smokers to quit tobacco altogether".

The report - which was heavily criticised - said any new regulations should "maximise the public health opportunities of electronic cigarettes".

It added: "While vaping may not be 100% safe, most of the chemicals causing smoking-related disease are absent and the chemicals which are present pose limited danger."

According to Nice, smoking is the main cause of preventable illness and premature death in England.

In 2014/15, an estimated 475,000 NHS hospital admissions in England were linked to smoking and 17% (78,000) of all deaths in 2014 were attributed to smoking.

Treating smoking-related illness is estimated to cost the NHS £2.5 billion a year while the wider cost to society is about £12.7 billion.

Professor Gillian Leng, deputy chief executive at Nice, said: "The guideline committee found little evidence of the long-term effects of e-cigarettes on human health and subsequently their use was not included as a recommended aid to stop smoking.

"However, Nice is keen to hear feedback on the use of e-cigarettes during the consultation on this guideline.

"We acknowledge that Public Health England and the Royal College of Physicians have stated that e-cigarettes are significantly less harmful to health than tobacco.

"This has been included in the guideline along with the recommendation that patients should receive advice on e-cigarettes so that they can make informed decisions on how to stop smoking."

Trending

Best friends keep their hands in The Cookie Jar in Leyland

Feature: ‘Crisis’ on the buses

Ellie-May death trial: Mum and boyfriend from Preston jailed over death of tragic toddler